342 
MANGANESE DEPOSITS OF INDIA : GEOLOGY. [PaRT TI : 
Narukot, however, the calcareous manganiferous sediments were 
deposited in such intimate association with the arenaceous and 
argillaceous manganiferous sediments that it is impossible to separate 
them now that they have been folded together and metamorphosed. 
The consequence is that in both these areas piedmontite-bearing 
members of the gondite series are found, together with other rocks 
characterized by a high percentage of calcareous matter. Thus in 
Jhabua there are the rocks containing winchite and calcite, and in 
Narukot rocks containing calcite and woUastonite. 
In both the Central Provinces and Jhabua arsenates have been 
found forming important constituents in masses 
Arsenates in the i i i • i • 
gondite series. of rock belongmg to this series. In the one case 
in the Central Provinces, namely at Sitapar in 
the Chhindwara district, the arsenate is associated with various 
manganese-ores, so that in this case it may not have been produced 
by the direct metamorphism of original sediments, but by the subsequent 
action of mineralized waters. This, however, is by no means certainly 
the case, and, from the nature of the minerals with which the arsenate 
is associated, it is quite possible that the arsenate and the minerals with 
which it occurs are the products cf the metamorphism of sediments con- 
taining arsenic, the metamorphic processes having possibly been aided 
by circiilatiug waters bringing about a concentration of the perhaps 
originally more uniformly distributed arsenic. In the uther case of a 
rock containing an arsenate, namely at Kajlidcngri in Jhabua, the rock 
must be regarded as the direct product of metamorphism of the original 
sediments, for it is in all respects like other members of this series, except 
that it contains an arsenate as a very important constituent. The exact 
composition of these arsenates has not yet been determined, but calcium 
and magnesium sesm to be important constituents in Jhabua and 
calcium in the Central Provinces } 
Besides rhodonite, other pyroxenes are sometimes, though very rarely, 
Pyroxenes in the foimd in the Tocks of this Series. These pyrcxenet; 
pondite -series. ];^a,ve not yet been examined in detail, but as seen 
under the microscope they usually show not very strongly marked pleo- 
cbroism in shades of yellow and brown, so that they maybe allied to the 
manganese-pyroxene, schefferite. 8uch pyroxenti are especially 
abundant at Jothvad in Narukot, but have also been foond m the 
Central Provinces and Jhabua. 
1 'I'ho Sitapar mineral is partly phosphate. 
